194878081 has 4 divisors (see below), whose sum is σ = 195100164. Its totient is φ = 194656000.

The previous prime is 194878063. The next prime is 194878097. The reversal of 194878081 is 180878491.

194878081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 80730225 + 114147856 = 8985^2 + 10684^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-194878081 is a prime.

It is a super-2 number, since 2×194878081² = 75954932908485122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (194878181) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 109720 + ... + 111481.

It is an arithmetic number, because the mean of its divisors is an integer number (48775041).

Almost surely, 2^194878081 is an apocalyptic number.

It is an amenable number.

194878081 is a deficient number, since it is larger than the sum of its proper divisors (222083).

194878081 is an equidigital number, since it uses as much as digits as its factorization.

194878081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222082.

The product of its (nonzero) digits is 129024, while the sum is 46.

The square root of 194878081 is about 13959.8739607491. The cubic root of 194878081 is about 579.7681207453.

The spelling of 194878081 in words is "one hundred ninety-four million, eight hundred seventy-eight thousand, eighty-one".